The invention relates to a method for conveying relatively voluminous packing units, such as containers, more in particular containers in shipping ports, wherein each packing unit can be separately displaced by a conveying means and the packing unit is conveyed, independently of further packing units, from a put-on location to a take-off location, and an apparatus for carrying out such method, as known from NL-A-760030g and NL-A-7108444.
In the dock industry, such method is known for the automized conveyance of containers, wherein up to the present, centrally controlled individually operating robot vehicles, better known as Automatic Guided Vehicles (AGVs) have been employed because of the individual collecting and delivery addresses that are specific for each container.
It has been found that a conveying system having AGVs can only provide a limited maximum conveying capacity at a relatively small number of AGVs deployed. When more AGVs are deployed, the effective capacity rapidly decreases because of the delay caused by AGVs disturbing one another in their movements when travelling back and forth loaded or unloaded. This problem could be solved through the use of conveying tracks as known in production and distribution environments, inter alia for, providing a continuous conveyance of goods from one location to the other. Although such conveying tracks are extremely suitable for mass transport, the conveyed goods cannot follow individual routes.
The object of the invention is to improve the method described in the opening paragraph in such a manner that the conveying capacity is extended considerably, while the possibility of having the goods follow individual routes is maintained.
According to the invention, this object is realized in that by a first conveying means, which carries a packing unit and which is fixedly disposed, a displacement is imposed on that packing unit in a direction towards a connecting, fixedly disposed second conveying means, and the packing unit is thus transferred to the second conveying means, which maintains or changes the direction of the displacement during the transfer of the packing unit to a connecting, fixedly disposed third conveying means, depending on a pattern in which the interconnecting conveying means that are present are arranged and a desired path over those conveying means between the put-on location and the take-off location. Because of these features, a system of branched conveying paths can be obtained wherein it becomes possible, by virtue of the segmented construction of the system by means of the various stationary, interconnecting conveying means, drivable in a mutually independent manner, to have each packing unit follow its own individual path, while the advantage of a mass transport is entirely maintained.
A path to be followed by a packing unit can be established in advance, depending on the put-on and take-off locations. To enable processing a large number of packing units simultaneously and in a flexible and efficient manner, it is preferred that the path to be followed by each packing unit over the conveying means be determined by a central control which, depending on the intended take-off location and the place where the packing unit is currently located, successively activates the desired conveying means. The determination of the current location of a particular packing unit can readily be performed through the provision of an identification means on the packing unit and a fixedly disposed detecting mechanism connected to the central control, which detecting mechanism is preferably provided on each conveying means. To prevent thrusts by means of intermediate storage, it may further be provided that the activation of successively connecting conveying means for transferring a packing unit from one conveying means to the other is performed with time delay.
The invention also relates to an apparatus for carrying out a conveyance as discussed hereinabove. To that end, an apparatus comprising a number of separately drivable conveying means, each capable of carrying and displacing a packing unit to be conveyed, is constructed according to the invention in such a manner that the conveying means each comprise an independently drivable conveying track and are arranged so as to be stationary in at least two rows which intersect while enclosing an angle relative to each other, wherein a packing unit can be transferred, by a conveying means associated with one of the rows, to an adjacent conveying means associated with the same row, and of each row at least one of the conveying means associated with that row can transfer the packing unit to a conveying means associated with another row. Thus, the possibility of an optimum manoeuvrability can be created for handling a flow of packing units in a flexible and efficient fashion, while it is preferred that a number of transverse rows of conveying means connect perpendicularly to a first row of conveying means, and further that the transverse rows of conveying means be connected by at least one further row of conveying means, which row is disposed parallel to and spaced from the first-mentioned row of conveying means. In this manner, a network of conveying paths can be created, whereby the separate packing units can each be delivered at the desired location and the desired point of time. In order that the above proceeds as smoothly and effectively as possible, it is preferred that a detecting mechanism be provided for observing an identification means connected to each packing unit, which detecting mechanism is connected to a central control which can activate each conveying means individually for displacing the packing unit in the desired direction. The detecting mechanism can for instance be radiographically provided with information by the identification means of the various packing units. However, it is preferred that each conveying means be provided with a detecting mechanism connected to the central control.